Apparatus and method for communicating voice and data between a customer premises and a central office

• US 6,061,392 A
• Filed: 11/03/1997
• Issued: 05/09/2000
• Est. Priority Date: 12/17/1996
• Status: Expired due to Term

• Current Assignee: Paradyne Corporation (Dasan Networks Incorporated)
• Original Assignee: Paradyne Corporation (Dasan Networks Incorporated)
• Inventors: Bremer, Gordon, Bingel, Thomas
• Primary Examiner(s): VO, DON NGUYEN
• Application Number:
  US08/962,796
• Time in Patent Office: 918 Days
• Field of Search: 375/222, 370/433, 370/468, 370/493, 370/494, 370/495, 379/88.13, 379/93.01, 379/93.09
• US Class Current: 375/222
• CPC Class Codes: H04J 1/12 Arrangements for reducing cross-talk between channels in line transmission systems H04B3/32; in cables or lines H04B3/26 - H04B3/30
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 5/1438 Negotiation of transmission parameters prior to communication modified according to link quality H04L1/0001
• CPC Class Codes: H04M 11/062 using different frequency bands for speech and other data

Abstract

A method and apparatus are provided for communicating data across a communication link, in a manner that senses and dynamically adapts to the simultaneous transmission of voice information across the local loop. In accordance with one aspect of the invention, a method is provided for dynamically communicating data over a local loop using a modem comprising the steps of transmitting data in a full-band transmission state, sensing a band-limiting condition, and adjusting the transmission of data from the full-band transmission state to a bandlimited transmission state, in response to the sensing step. In accordance with the method, data may be transmitted by the modem across the local loop at the same time that voice information is communicated via telephone across the same local loop. A significant aspect of the present invention is the dynamic allocation of the data transmission bandwidth, whereby the invention senses a condition indicative of whether voice information is being communicated. If so, then the system shifts and/or narrows the data transmission bandwidth to allow for voice communications without interference from or with the data transmission. However, when no voice information is being communicated, the invention dynamically allocates the data transmission bandwidth to utilize at least a portion, if not all, of the frequency band otherwise used for communicating voice information.

Claims

1. A modem for communicating across a communication link comprising:

an input/output signal line in communication with the communication link;

a processor unit adapted for operation in one of at least two states, a full-band transmission state and a band-limited state, wherein the full-band transmission state is defined by significant transmission energy in a frequency range below a first frequency, and a band-limited transmission state defined by a negligible amount of energy in the frequency range below the first frequency and a significant amount of energy above the first frequency, wherein the first frequency is at least 4000 Hertz.

2. The modem as defined in claim 1, wherein the first frequency is approximately 15 kilohertz.

3. The modem as defined in claim 1, wherein the communication link is a multiple-use communication link.

4. The modem as defined in claim 1, further including:

sensing means for sensing a band-limiting condition; and

control means associated with the processor unit responsive to the sensing means for controlling the operating state of the processor unit, wherein upon sensing the band-limiting condition the control means causes the processor to operate in the band-limited state, and upon sensing no band-limiting condition the control means causes the processor to operate in the full-band transmission state.

5. The modem as defined in claim 1, wherein significant energy transmissions are transmissions substantially exceeding an audible level.

6. A modem for communicating across a communication link capable of single-use transmissions and multiple-use transmissions comprising:

an input/output signal line in communication with the communication link;

a processor unit adapted for operation in one of at least two states, a full-band transmission state and a band-limited state, the full-band transmission state defined by data transmission in a frequency band including frequencies above and below approximately 4000 Hertz and the band-limited state defined by data transmission in a frequency band including frequencies only above approximately 4000 Hertz, wherein the full-band transmission state occurs when single-use transmissions are occurring across the transmission link, and the band-limited transmission state occurs when multiple-use transmissions are occurring across the communication link.

7. A modem for communicating across a communication link comprising:

an input/output signal line in communication with the communication link;

a processor unit adapted for operation in one of at least two states, a full-band transmission state and a band-limited state, wherein the full-band transmission state is defined by significant energy transmission below a first frequency and the band-limited state is defined by substantially zero energy transmission below the first frequency wherein the first frequency is at least 4000 Hertz.;

sensing means for sensing a band-limiting condition; and

control means associated with the processor unit responsive to the sensing means for controlling the operating state of the processor unit, wherein upon sensing the band-limiting condition the control means causes the processor to operate in the band-limited state, and upon sensing no band-limiting condition the control means causes the processor to operate in the full-band transmission state.

8. The modem as defined in claim 7, wherein the first frequency is approximately 15 kilohertz.

9. The modem as defined in claim 7, wherein the sensing means is configured to detect a multi-position switch, the position of which defines the band-limiting condition.

10. The modem as defined in claim 7, wherein the sensing means is configured to detect an off-hook condition of a telephone that is electrically connected to the input/output signal line.

11. The modem as defined in claim 10, wherein the sensing means further includes means for detecting the onset of a condition indicative of a handset of the telephone being taken off-hook.

12. The modem as defined in claim 11, wherein the means for detecting the onset of the condition is configured to detect a voltage drop on the input/output signal line.

13. The modem as defined in claim 11, wherein the means for detecting the onset of the condition is configured to detect an impedance shift in the input/output signal line.

14. The modem as defined in claim 7, wherein the full-band transmission state is defined by a transmission frequency bandwidth having a lower frequency boundary of less than 4 kilohertz.

15. The modem as defined in claim 14, wherein the full-band transmission state is defined by a transmission frequency bandwidth having a lower frequency boundary of approximately DC.

16. The modem as defined in claim 7, wherein the full-band transmission state is defined by a transmission frequency bandwidth having an upper frequency boundary of greater than 50 kilohertz.

17. The modem as defined in claim 16, wherein the full-band transmission state is defined by a transmission frequency bandwidth having an upper frequency boundary of approximately 100 kilohertz.

18. The modem as defined in claim 7, wherein the band-limited transmission state is defined by a transmission frequency bandwidth having a lower frequency boundary of greater than 4 kilohertz.

19. The modem as defined in claim 18, wherein the full-band transmission state is defined by a transmission frequency bandwidth having a lower frequency boundary of approximately 20 kilohertz.

20. The modem as defined in claim 7, wherein the full-band transmission state is defined by a first transmission frequency bandwidth and the band-limited transmission state is defined by a second transmission frequency bandwidth, wherein the first transmission frequency bandwidth has an upper frequency boundary that is substantially the same an upper frequency boundary of the second frequency bandwidth.

21. The modem as defined in claim 7, wherein the full-band transmission state is defined by a first transmission frequency bandwidth and the band-limited transmission state is defined by a second transmission frequency bandwidth, wherein the first transmission frequency bandwidth has an upper frequency boundary that is different than an upper frequency boundary of the second frequency bandwidth.

22. The modem as defined in claim 7, wherein the communication link is a two-wire telecommunications link.

23. The modem as defined in claim 7, wherein the communication link is a local loop.

24. The modem as defined in claim 7, wherein the sensing means includes a code segment containing executable code.

25. The modem as defined in claim 7, wherein the control means includes a code segment containing executable code.

26. A modem for communicating across a communication link comprising:

an input/output signal line in communication with the communication link;

a processor unit adapted for operation in one of two states, a full-band transmission state and a band-limited state, wherein the full-band transmission state is defined by a lower frequency boundary below a second frequency and an upper frequency boundary greater than a first frequency, and the band-limited state is defined by a lower frequency boundary greater than the second frequency and an upper frequency boundary greater than the first frequency, wherein the first frequency is approximately 4000 Hertz;

a sensor configured to detect the presence of a band-limiting condition; and

a controller associated with the processor unit and responsive to the sensor, configured to control the operating state of the processor unit, wherein upon sensing the band-limiting condition the controller causes the processor to operate in the band-limited state, and upon sensing no band-limiting condition the controller causes the processor to operate in the full-band transmission state.

27. The modem as defined in claim 26, wherein the first frequency is approximately 50 kilohertz.

28. The modem as defined in claim 26, wherein the second frequency is approximately 4 kilohertz.

29. A method for dynamically communicating data over a communication link using a modem comprising the steps of transmitting data in a full-band transmission state, wherein the full-band transmission state is defined by a frequency band having a lower boundary below 4000 Hertz and an upper boundary above 4000 Hertz;

sensing a band-limiting condition; and

adjusting the transmission of data from the full-band transmission state to a band-limited transmission state, in response to the sensing step, wherein the band-limited transmission state is defined by a frequency band entirely above 4000 Hertz.

30. The method as defined in claim 29, wherein the sensing step includes detecting the position of a multi-position switch.

31. The method as defined in claim 29, further including the step of adaptively varying transmit power of the transmission of data to minimize interference of data signals with a lower frequency band.

32. The method as defined in claim 29, further including the step of uniquely shaping a power spectral transmission band of the data transmission to minimize interference of data signals with a lower frequency band.

33. The method as defined in claim 29, further including the step of sensing a cessation of the band-limiting condition.

34. The method as defined in claim 33, further including the step of adjusting the transmission of data from the band-limited transmission state to the full-band transmission state, in response to the step of sensing the cessation of the band-limiting condition.

35. The method as defined in claim 29, wherein the step of sensing the band-limiting condition includes sensing an incoming ring signal on the communication link.

36. The method as defined in claim 29, wherein the step of sensing a band-limiting condition includes sensing an off-hook condition of a telephone handset of a telephone electrically connected to the communication link.

37. The method as defined in claim 36, wherein the step of sensing the off-hook condition includes sensing an impedance of the communication link.

38. The method as defined in claim 36, wherein the step of sensing the off-hook condition includes sensing a voltage on the communication link.

39. The method as defined in claim 29, wherein the full-band transmission state is defined by a transmission frequency bandwidth having a lower frequency boundary of less than 4 kilohertz.

40. The method as defined in claim 39, wherein the full-band transmission state is defined by a transmission frequency bandwidth having a lower frequency boundary of approximately DC.

41. The method as defined in claim 29, wherein the full-band transmission state is defined by a transmission frequency bandwidth having an upper frequency boundary of greater than 50 kilohertz.

42. The method as defined in claim 41, wherein the full-band transmission state is defined by a transmission frequency bandwidth having an upper frequency boundary of approximately 100 kilohertz.

43. The method as defined in claim 29, wherein the band-limited transmission state is defined by a transmission frequency bandwidth having a lower frequency boundary of greater than 4 kilohertz.

44. The method as defined in claim 43, wherein the full-band transmission state is defined by a transmission frequency bandwidth having a lower frequency boundary of approximately 20 kilohertz.

45. The method as defined in claim 29, wherein the full-band transmission state is defined by a first transmission frequency bandwidth and the band-limited transmission state is defined by a second transmission frequency bandwidth, wherein the first transmission frequency bandwidth has an upper frequency boundary that is substantially the same an upper frequency boundary of the second frequency bandwidth.

46. The method as defined in claim 29, wherein the full-band transmission state is defined by a first transmission frequency bandwidth and the band-limited transmission state is defined by a second transmission frequency bandwidth, wherein the first transmission frequency bandwidth has an upper frequency boundary that is different than an upper frequency boundary of the second frequency bandwidth.

47. A method for dynamically communicating data across a communication link using a modem comprising the steps of:

transmitting data in a band-limited transmission state, wherein the band-limited transmission state is defined by a frequency band entirely above 4000 Hertz;

sensing a cessation in a band-limiting condition; and

adjusting the transmission of data from the band-limited transmission state to a full-band transmission state, in response to the sensing step, wherein the full-band transmission state is defined by a frequency band extending at least partially below 4000 Hertz.

48. The method as defined in claim 47, further including the step of sensing a band-limiting condition.

49. The method as defined in claim 48, further including the step of adjusting the transmission of data from the full-band transmission state to the band-limited transmission state, in response to the step of sensing the band-limiting condition.

50. A modem for communicating across at least two channels of a communication link comprising:

means for defining a first communication channel having a dynamic bandwidth, the first communication channel having a full-band transmission state and a band-limited transmission state, wherein the full-band transmission state is defined by a frequency band that at least partially extends below 4000 Hertz, and the band-limited transmission state is defined by a frequency band that is entirely above 4000 Hertz;

means for accommodating a second communication channel;

means for controlling the communication across the first communication channel such that the communication is in the full-band transmission state when no communications are occurring across the second communication channel, and the communication is in the band-limited transmission state when communications are occurring across the second communication channel.

51. The modem as defined in claim 50, wherein the second communication channel is a POTS communication channel.

52. The modem as defined in claim 51, wherein information transmitted across the second communication channel is voice information.

53. The modem as defined in claim 51, wherein information transmitted across the second communication channel is data communicated from a PSTN modem.

54. A modem for communicating across at least two channels of a communication link comprising:

circuitry configured to define a first communication channel having a dynamic bandwidth, the first communication channel having a full-band transmission state defined by a frequency band that extends at least partially below 4000 Hertz, and a band-limited transmission state, defined by a frequency band that exists entirely above 4000 Hertz;

circuitry configured to accommodate a second communication channel;

circuitry configured to control the communication across the first communication channel such that the communication is in the full-band transmission state when no communications are occurring across the second communication channel, and the communication is in the band-limited transmission state when communications are occurring across the second communication channel.